Airfoil leading edges and nose cones of aircraft are susceptible to erosion caused by debris and/or weathering. As such, currently in industry, protective film or erosion caps are used to protect leading edges of airfoils and nose cones from erosion. For example, a known polyurethane protective tape has been used on airfoil leading edges to protect them from erosion. However, this is a flat tape and it does not have a contoured shape specific to the airfoil. At least one known aircraft includes winglets having a protective film covering on the leading edge of the winglet. Known erosion caps include contoured metal sheets mechanically fastened to the airfoil leading edge. These erosion caps extend rearwardly covering about ten (10) percent (%) of the chord length. As such, the mechanical fasteners and the back edge of the erosion cap disturbs the laminar flow. Such protective coverings and erosion caps are manufactured to only extended rearwardly covering about 10% of the chord length to save on weight and cost.
In addition, laminar flow across a winglet or other airfoil is also disturbed by steps that are formed from the layers of paint on the winglet (e.g., painting on the winglet is done by applying multiple single-color paint layers, and steps are formed between the successive layers of paint). The disruption of laminar flow by the back edge of the protective covering or erosion cap and/or by the paint steps increases the drag across the airfoil and reduces fuel efficiency.
Therefore, an improved protective finish for wing tip devices is needed.